What happened

I think the old-fashioned word (like last month) was "review," which is mentioned in the question. My guess is that the word "debrief" may have come into play when a consulting company was pretending to have a new or different concept for the well established routine that professionals in your field already know about. Consulting companies tend to do that when they don't have anything special to offer. They sell the use of new words that generally only tend to confuse the work process.

I don't connect "debrief" with the military as much as with formality. It connotes to me a more formal closure to an event than a mere review. If I attend a formal meeting, I am often "briefed" prior to it. During the session the disicussion is "reviewed" by the participants. Following the meeting I may have to "brief" my management, or to put it another way I get "debriefed". The terms seem to convey precisely the meaning intended, so I am not sure another word is needed. As a side note, "debriefing" meant something else when I was in school, and was extremely uncomfortable. Business "debriefings" are no different.